How to modify a DTP filter parameter list in BI 7.4

Hello,

I'm trying to add filters to a DTP in BI 7.4.  Some of the fields are not on the initial field list (but are in the source object).  When the "Change Selection" button is selected...a list of entries comes up with check-boxes.  However, some of the fields I require are still not on this second list.

Is there a way to modify this list (title of pop-up is "Selection of Fields")?  On what basis are the fields that appear on this list chosen?

I recall from earlier versions of BI that there were two windows; List of available fields in source object & List of fields selected as filter parameters.......and you would simply move the fields you required from one to the other.

Thanks in advance......Chris